1. Field of the Invention
This invention relates to wireless communication systems, and more particularly to a wireless communication system with native redundancy, which provides improved data connectivity to a plurality of customers.
2. Description of Related Art
Several systems are currently in place for connecting computer customers to one another and to the Internet. For example, many companies such as Cisco Systems, provide data routers that route data from personal computers and computer networks to the Internet along conventional twisted pair wires and fiber optic lines. These same systems are also used to connect separate offices together in a wide area data network.
However, these systems suffer significant disadvantages because of the time and expense required to lay high capacity communications cables between each office. This process is time consuming and expensive. What is needed in the art is a high capacity system that provides data links between offices, but does not require expensive communication cables to be installed.
Many types of current wireless communication systems facilitate two-way communication between a plurality of subscriber radio stations or subscriber units (either fixed or portable) and a fixed network infrastructure. Exemplary systems include mobile cellular telephone systems, personal communication systems (PCS), and cordless telephones. The objective of these wireless communication systems is to provide communication channels on demand between the subscriber units and the base station in order to connect the subscriber unit customer with the fixed network infrastructure (usually a wired-line system). Several types of systems currently exist for wirelessly transferring data between two sites. For example, prior art wireless communication systems have typically used a Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA) or Frequency Division Multiple Access (FDMA) type system to facilitate the exchange of information between two customers. These access schemes are well known in the art.
As can be imagined, in any of these types of wireless communication systems there are many components within the system that may fail at any time and result in the communication link being lost. When a single point failure occurs, the subscriber is unable to connect or continue sending information through the data channel to the base station. Should this repeatedly occur, for example in a system with a low mean time between failures (xe2x80x9cMTBFxe2x80x9d), the subscriber may become dissatisfied with their wireless communication system and discontinue the service.
Traditionally, to overcome a potential system failure and maintain high subscriber satisfaction, redundant or back-up components are incorporated into the wireless communication system. While these additional components may improve the wireless communication system""s MTBF, significant costs are incurred in incorporating the components. Often, nearly a one to one ratio of primary components to backup components is used to ensure a single point failure will not occur. However, even when back-up components are used, the complexity of the wireless communication system is further exacerbated since once a failure does occurs, elaborate switching and hand-offs must be designed into the wireless communication system to reestablish the data link with the remaining primary components.
Consequently, a need remains for a wireless communication system without the complexity of incorporating multiple redundancy system while maintaining the system reliability demanded by today""s high technology subscriber. It is also desirable to provide a system for switching around a failed component without requiring elaborate switching and hand-offs between the primary and back-up components.
The systems and methods of the present invention have several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this invention as expressed by the claims which follow, its more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled xe2x80x9cDetailed Description of the Inventionxe2x80x9d one will understand how the features of this invention provide several advantages over traditional paper coupon systems.
Another aspect of the invention is a redundancy system of primary components and standby components comprising a plurality of primary modem interface for modulating/demodulating data transmitted between a base station and a customer, a plurality of primary outdoor units wherein each of the primary outdoor units is in data communication with one of the plurality of primary modem interface wherein each of the primary outdoor units comprises a transceiver for transmitting and receiving data from the customer, a standby modem interface for modulating/demodulating data transmitted between the base station and the customer, a plurality of standby outdoor units each comprising a second transceiver for transmitting and receiving data from the customer, wherein the plurality of standby outdoor units is in data communication with the standby modem interface, and wherein each of the plurality of standby outdoor units is configured to replace one of the plurality of primary outdoor units, a redundancy card comprising a selectable switch wherein the selectable switch is in communication with the standby modem interface and the plurality of standby outdoor units to allow data communication between the standby modem interface and one of the plurality of standby outdoor units whereby data communication is maintained between the customer and the base station when one of the plurality of primary modem interfaces or one of the plurality of primary outdoor units is unavailable.
One aspect of the present invention is a method of using a redundancy system of primary components and standby components in a wireless communication system. The method includes receiving a fault message from an originating primary component, correlating the fault message with additional primary components in the wireless communication system, determining whether the fault message affects system level operation, and switching over from the originating primary component to a standby component based on said determination.